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1.
Dalton Trans ; 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39233530

RESUMO

Herein, we describe the synthesis and characterization of a series of thiosemicarbazone platinacycles. Their activity towards HCT116 and A2780 cancer cell lines as well as normal fibroblasts was explored and conclusions about the influence of their structures were drawn based on the results. Ligands L1-3, tetranuclear compounds [Pt(L1-3)]4, [Pt(L1-3)(PPh3)], and [Pt(L1-L3)2{Ph2P(CH2)4PPh2}], and phosphine derivatives, were deemed unpromising owing to their lack of activity. However, mono-coordinated diphosphine complexes [Pt(L1-L3)(Ph2PCH2PPh2-P)] showed high selectivity and low IC50 values, and their antiproliferative activity was further studied. The three studied derivatives 3a, 3b and 3c showed a fast internalization of HCT116 colorectal cancer cells with similar IC50 values, which induced a depolarization of mitochondrial membrane potential, with the subsequent triggering of apoptosis and autophagy in the case of 3c. In the case of compounds 3a and 3b, cell death mechanisms (extrinsic and intrinsic apoptosis, respectively) were triggered via the induction of reactive oxygen species (ROS). The three compounds were not toxic to a chicken embryo in vivo (after 48 h), and, importantly, showed an anti-angiogenic potential after exposure to the IC50 of compounds 3a, 3b and 3c.

2.
Front Chem ; 12: 1379914, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39170866

RESUMO

The rise of antibiotic-resistant bacterial strains has become a critical health concern. According to the World Health Organization, the market introduction of new antibiotics is alarmingly sparse, underscoring the need for novel therapeutic targets. The LytR-CpsA-Psr (LCP) family of proteins, which facilitate the insertion of cell wall glycopolymers (CWGPs) like teichoic acids into peptidoglycan, has emerged as a promising target for antibiotic development. LCP proteins are crucial in bacterial adhesion and biofilm formation, making them attractive for disrupting these processes. This study investigated the structural and functional characteristics of the LCP domain of LytR from Streptococcus dysgalactiae subsp. dysgalactiae. The protein structure was solved by X-ray Crystallography at 2.80 Å resolution. Small-angle X-ray scattering (SAXS) data were collected to examine potential conformational differences between the free and ligand-bound forms of the LytR LCP domain. Additionally, docking and molecular dynamics (MD) simulations were used to predict the interactions and conversion of ATP to ADP and AMP. Experimental validation of these predictions was performed using malachite green activity assays. The determined structure of the LCP domain revealed a fold highly similar to those of homologous proteins while SAXS data indicated potential conformational differences between the ligand-free and ligand-bound forms, suggesting a more compact conformation during catalysis, upon ligand binding. Docking and MD simulations predicted that the LytR LCP domain could interact with ADP and ATP and catalyze their conversion to AMP. These predictions were experimentally validated by malachite green activity assays, confirming the protein's functional versatility. The study provides significant insights into the structural features and functional capabilities of the LCP domain of LytR from S. dysgalactiae subsp. dysgalactiae. These findings pave the way for designing targeted therapies against antibiotic-resistant bacteria and offer strategies to disrupt bacterial biofilm formation.

3.
GE Port J Gastroenterol ; 31(4): 225-235, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39022303

RESUMO

Pancreatic neuroendocrine tumors (panNETs) are a group of neoplasms with heterogenous biological and clinical phenotypes. Although historically regarded as rare, the incidence of these tumors has been increasing, mostly owing to improvements in the detection of small, asymptomatic tumors with imaging. The heterogeneity of these lesions creates significant challenges regarding diagnosis, staging, and treatment. Endoscopic ultrasound (EUS) has improved the characterization of pancreatic lesions. Furthermore, EUS nowadays has evolved from a purely diagnostic modality to allow the performance of minimally invasive locoregional therapy for pancreatic focal lesions. The choice of treatment as well as the treatment goals depend on several factors, including tumor secretory status, grading, staging, and patient performance status. Surgery has been the mainstay for the management of these patients, particularly for localized, low-grade, large panNETs >2 cm. Over the last decade, a significant body of evidence has been accumulated evaluating the role of EUS for the ablative therapy of panNETs, namely by the use of chemoablative agents and radiofrequency. Although endoscopic techniques are not routinely recommended by international guidelines, they may be considered for the treatment of smaller lesions in patients who are unwilling or unfit for pancreatic surgery. In this review, we summarize the existing evidence on the interventional techniques for the treatment of patients with panNETs, focusing on the EUS-guided and surgical approaches.


Os tumores neuroendócrinos do pâncreas (panNETs) são um grupo de neoplasias com comportamento biológico e clínico heterogéneo. Embora historicamente considerados raros, a incidência desses tumores tem aumentado, algo que se atribui principalmente à melhoria na deteção de pequenos tumores assintomáticos em exames de imagem. A heterogeneidade destas lesões cria desafios significativos no que respeita ao seu diagnóstico, estadiamento e tratamento. A ultrassonografia endoscópica melhorou a caracterização das lesões pancreáticas. Concomitantemente, a ultrassonografia endoscópica, para além da vertente diagnóstica, evoluiu no sentido do desenvolvimento de capacidades terapêuticas, permitindo a realização de terapêutica locorregional de lesões pancreáticas focais de forma minimamente invasiva.A seleção do tratamento, bem como a definição dos seus objetivos, depende de diversos fatores, incluindo a atividade secretora da neoplasia, a sua atividade mitótica, o estadiamento e o status funcional do doente. A cirurgia é considerada a pedra basilar do tratamento destes doentes, particularmente para panNETs localizados, de baixo grau, com >2 cm. Ao longo da última década foi gerado um conjunto significativo de evidência relativamente ao papel da ultrassonografia endoscópica na terapêutica ablativa dos panNETs, nomeadamente através da utilização de agentes quimioablativos e de radiofrequência. Embora as recomendações internacionais não recomendem a utilização rotineira destas técnicas para o tratamento dos panNETs, as mesmas podem ser consideradas no tratamento de lesões de menores dimensões em doentes que não desejem ou que sejam considerados inaptos para cirurgia pancreática. Esta revisão visa resumir a evidência existente relativa às técnicas de intervenção para o tratamento de pacientes com panNETs, com foco nas abordagens cirúrgica e guiada por ultrassonografia endoscópica.

4.
Nanoscale ; 16(32): 15176-15195, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39052238

RESUMO

In this work, we report the disruptive use of membrane-localized magnetic hyperthermia to promote the internalization of cell-impermeant probes. Under an alternating magnetic field, magnetic nanoparticles (MNPs) immobilized on the cell membrane via bioorthogonal click chemistry act as nanoheaters and lead to the thermal disruption of the plasma membrane, which can be used for internalization of different types of molecules, such as small fluorescent probes and nucleic acids. Noteworthily, no cell death, oxidative stress and alterations of the cell cycle are detected after the thermal stimulus, although cells are able to sense and respond to the thermal stimulus through the expression of different types of heat shock proteins (HSPs). Finally, we demonstrate the utility of this approach for the transfection of cells with a small interference RNA (siRNA), revealing a similar efficacy to a standard transfection method based on the use of cationic lipid-based reagents (such as Lipofectamine), but with lower cell toxicity. These results open the possibility of developing new procedures for "opening and closing" cellular membranes with minimal disturbance of cellular integrity. This on-demand modification of cell membrane permeability could allow the direct intracellular delivery of biologically relevant (bio)molecules, drugs and nanomaterials, thus overcoming traditional endocytosis pathways and avoiding endosomal entrapment.


Assuntos
Membrana Celular , Nanopartículas de Magnetita , Humanos , Membrana Celular/metabolismo , Nanopartículas de Magnetita/química , RNA Interferente Pequeno/metabolismo , RNA Interferente Pequeno/química , Permeabilidade da Membrana Celular , Hipertermia Induzida , Corantes Fluorescentes/química , Transfecção , Células HeLa , Endocitose , Campos Magnéticos
5.
Neuron ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39047728

RESUMO

Activity-dependent modulations of N-methyl-D-aspartate glutamate receptor (NMDAR) trapping at synapses regulate excitatory neurotransmission and shape cognitive functions. Although NMDAR synaptic destabilization has been associated with severe neurological and psychiatric conditions, tuning NMDAR synaptic trapping to assess its clinical relevance for the treatment of brain conditions remains a challenge. Here, we report that ketamine (KET) and other clinically relevant NMDAR open channel blockers (OCBs) promote interactions between NMDAR and PDZ-domain-containing scaffolding proteins and enhance NMDAR trapping at synapses. We further show that KET-elicited trapping enhancement compensates for depletion in synaptic receptors triggered by autoantibodies from patients with anti-NMDAR encephalitis. Preventing synaptic depletion mitigates impairments in NMDAR-mediated CaMKII signaling and alleviates anxiety- and sensorimotor-gating-related behavioral deficits provoked by autoantibodies. Altogether, these findings reveal an unexpected dimension of OCB action and stress the potential of targeting receptor anchoring in NMDAR-related synaptopathies.

6.
ChemMedChem ; : e202400225, 2024 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-38880774

RESUMO

Azaindole scaffold is a privileged structure in medicinal chemistry and some derivatives have demonstrated to be potential anticancer drugs. Herein, a set of novel azaindoles, comprising the four regioisomers, bearing a morpholine (azaindoles 3a-d) and N-methyl-N-benzylamine (azaindoles 4a-d) groups were prepared. Among these compounds, azaindoles 4 exhibited higher cytotoxicity against the ovarian cancer cell line A2780 and normal dermal fibroblasts compared to azaindoles 3. Furthermore, azaindoles 4b and 4c promoted a delay in the cell cycle of the cancer cell line, inspiring an investigation into the intracellular localization of these derivatives.

7.
GE Port J Gastroenterol ; 31(3): 153-164, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38836119

RESUMO

Pancreatic neuroendocrine neoplasms (panNENs) have been historically regarded as rare, but their incidence has raised more than 6-fold over the last 3 decades, mostly owing to improvement in the detection of small asymptomatic tumours with imaging. Early detection and proper classification and staging are essential for the prognosis and management of panNENs. Histological evaluation is mandatory in all patients for the diagnosis of panNEN. Regarding localization and staging, multiphasic contrast-enhanced computer tomography is considered the imaging study of choice. Nevertheless, several other diagnostic modalities might present complementary information that can help in diagnosis and staging optimization: magnetic resonance imaging, somatostatin receptor imaging using positron emission tomography in combination with computed tomography (PET/CT), PET/CT with fluorodeoxyglucose (18F-FDG), and endoscopic ultrasound. Approximately 10% of panNENs are due to an inherited syndrome, which includes multiple endocrine neoplasia type 1, von Hippel-Lindau disease, neurofibromatosis type 1 (NF-1), tuberous sclerosis complex, and Mahvash disease. In this review, the Portuguese Pancreatic Club summarizes the classification, diagnosis, and staging of panNENs, with a focus on imaging studies. It also summarizes the characteristics and particularities of panNENs associated with inherited syndromes.


As neoplasias neuroendócrinas pancreáticas (panNENs) são historicamente consideradas raras, embora a sua incidência tenha aumentado mais de 6 vezes nas últimas três décadas, principalmente devido à otimização do diagnóstico de tumores pequenos e assintomáticos em exames de imagem. A deteção precoce, a classificação e o estadiamento adequados são essenciais para o prognóstico e abordagem dos panNENs. A avaliação histológica é obrigatória em todos os doentes para o diagnóstico de panNENs. Para a localização e estadiamento, ​​a TC multifásica com contraste é considerada o estudo de imagem de eleição. Contudo, várias outras modalidades diagnósticas podem apresentar informações complementares que podem auxiliar no diagnóstico e na otimização do estadiamento: ressonância magnética, PET/CT dos receptores da somatostatina, PET/CT [18F]FDG e ecoendoscopia. Aproximadamente 10% dos panNENs estão relacionados com síndromes hereditários, que incluem neoplasia endócrina múltipla tipo 1 (MEN1), doença de von Hippel-Lindau (VHL), neurofibromatose tipo 1 (NF1), complexo de esclerose tuberosa (TSC) e doença de Mahvash. Neste artigo, o Clube Português de Pâncreas aborda a classificação, diagnóstico e estadiamento de panNENs, ​​com foco nos estudos de imagem, bem como resume as características e particularidades dos panNENs associados aos síndromes hereditários.

9.
Talanta ; 274: 126052, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38608633

RESUMO

Lung cancer (LC) is a leading cause of global cancer-related deaths, highlighting the development of innovative methods for biomarker detection improving the early diagnostics. microRNAs (miRs) alterations are known to be involved in the initiation and progression of human cancers and can act as biomarkers for diagnostics and treatment. Herein, we develop the application of molecular beacon (MB) technology to monitor miR-155-3p expression in human lung adenocarcinoma A549 cells without complementary DNA synthesis, amplification, or expensive reagents. Furthermore, we produced gold nanoparticles (AuNPs) for delivering antisense oligonucleotides into A549 cells to reduce miR-155-3p expression, which was subsequently detectable using the MB. The MB was designed and structural characterized by Förster Resonance Energy Transfer (FRET)-melting, Circular Dichroism (CD), Nuclear magnetic resonance (NMR), and fluorometric experiments, and then the hybridization conditions were optimized for an in vitro approach involving the detection of miR-155-3p in total RNA extracted from A549 cell line. The expression profile of miR-155-3p was obtained by RT-qPCR. The results demonstrated that MB was properly designed and showed efficacy in targeting miR-155-3p. Furthermore, a limit of detection down to nanomolar concentration was achieved and the specificity of the biosensor was proved. Moreover, the self-assembly of ASOs with AuNPs exhibited exceptional target specificity, effectively silencing miR-155-3p. Notably, compared to lipid-based transfection agent, AuNPs displayed superior silencing efficiency. We highlighted the ability of MB to detect changes in the target gene expression after gene silencing. Overall, this innovative approach represents a promising tool for detecting various biomarkers at the same time, with potential applications in clinical settings.


Assuntos
Adenocarcinoma de Pulmão , Ouro , Neoplasias Pulmonares , Nanopartículas Metálicas , MicroRNAs , Humanos , MicroRNAs/genética , Ouro/química , Nanopartículas Metálicas/química , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Células A549 , Inativação Gênica
10.
Inorg Chem ; 63(13): 5783-5804, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38502532

RESUMO

In recent years, organometallic complexes have attracted much attention as anticancer therapeutics aiming at overcoming the limitations of platinum drugs that are currently marketed. Still, the development of half-sandwich organometallic cobalt complexes remains scarcely explored. Four new cobalt(III)-cyclopentadienyl complexes containing N,N-heteroaromatic bidentate, and phosphane ligands were synthesized and fully characterized by elemental analysis, spectroscopic techniques, and DFT methods. The cytotoxicity of all complexes was determined in vitro by the MTS assay in colorectal (HCT116), ovarian (A2780), and breast (MDA-MB-231 and MCF-7) human cancer cell lines and in a healthy human cell line (fibroblasts). The complexes showed high cytotoxicity in cancer cell lines, mostly due to ROS production, apoptosis, autophagy induction, and disruption of the mitochondrial membrane. Also, these complexes were shown to be nontoxic in vivo in an ex ovo chick embryo yolk sac membrane (YSM) assay.


Assuntos
Antineoplásicos , Complexos de Coordenação , Neoplasias Ovarianas , Animais , Embrião de Galinha , Humanos , Feminino , Linhagem Celular Tumoral , Antineoplásicos/química , Platina/farmacologia , Cobalto/farmacologia , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Apoptose
11.
J Med Chem ; 67(7): 5813-5836, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38518246

RESUMO

Eight 2,2':6',2″-terpyridines, substituted at the 4'-position with aromatic groups featuring variations in π-conjugation, ring size, heteroatoms, and methoxy groups, were employed to enhance the antiproliferative potential of [Cu2Cl2(R-terpy)2](PF6)2. Assessing the cytotoxicity in A2780 (ovarian carcinoma), HCT116 (colorectal carcinoma), and HCT116DoxR (colorectal carcinoma resistant to doxorubicin) and normal primary fibroblasts revealed that Cu(II) complexes with 4-quinolinyl, 4-methoxy-1-naphthyl, 2-furanyl, and 2-pyridynyl substituents showed superior therapeutic potential in HCT116DoxR cells with significantly reduced cytotoxicity in normal fibroblasts (42-129× lower). Besides their cytotoxicity, the Cu(II) complexes are able to increase intracellular ROS and interfere with cell cycle progression, leading to cell death by apoptosis and autophagy. Importantly, they demonstrated antimetastatic and antiangiogenic properties without in vivo toxicity. In accordance with their nuclear accumulation, the Cu(II) complexes are able to cleave pDNA and interact with bovine serum albumin, which is a good indication of their ability for internalization and transport toward tumor cells.


Assuntos
Antineoplásicos , Neoplasias Colorretais , Complexos de Coordenação , Neoplasias Ovarianas , Humanos , Feminino , Linhagem Celular Tumoral , Cobre/química , Antineoplásicos/farmacologia , Antineoplásicos/química , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Apoptose , Proliferação de Células , Cristalografia por Raios X
12.
Front Bioeng Biotechnol ; 12: 1320729, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38410164

RESUMO

Three-dimensional (3D) cell culture using tumor spheroids provides a crucial platform for replicating tissue microenvironments. However, effective gene modulation via nanoparticle-based transfection remains a challenge, often facing delivery hurdles. Gold nanoparticles (AuNPs) with their tailored synthesis and biocompatibility, have shown promising results in two-dimensional (2D) cultures, nevertheless, they still require a comprehensive evaluation before they can reach its full potential on 3D models. While 2D cultures offer simplicity and affordability, they lack physiological fidelity. In contrast, 3D spheroids better capture in vivo conditions, enabling the study of cell interactions and nutrient distribution. These models are essential for investigating cancer behavior, drug responses, and developmental processes. Nevertheless, transitioning from 2D to 3D models demands an understanding of altered internalization mechanisms and microenvironmental influences. This study assessed ASO-AuNP conjugates for silencing the c-MYC oncogene in 2D cultures and 3D tumor spheroids, revealing distinctions in gene silencing efficiency and highlighting the microenvironment's impact on AuNP-mediated gene modulation. Herein, we demonstrate that increasing the number of AuNPs per cell by 2.6 times, when transitioning from a 2D cell model to a 3D spheroid, allows to attain similar silencing efficiencies. Such insights advance the development of targeted gene therapies within intricate tissue-like contexts.

13.
Molecules ; 28(21)2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37959872

RESUMO

BACKGROUND: Antimicrobial resistance is one of the most pressing health issues of our time. The increase in the number of antibiotic-resistant bacteria allied to the lack of new antibiotics has contributed to the current crisis. It has been predicted that if this situation is not dealt with, we will be facing 10 million deaths due to multidrug resistant infections per year by 2050, surpassing cancer-related deaths. This alarming scenario has refocused attention into researching alternative drugs to treat multidrug-resistant infections. AIMS: In this study, the antimicrobial activities of four manganese complexes containing 1,2,3,-triazole and clotrimazole ligands have been evaluated. It is known that azole antibiotics coordinated to manganese tricarbonyl complexes display interesting antimicrobial activities against several microbes. In this work, the effect of the introduction of 1,2,3,-triazole-derived ligands in the [Mn(CO)3(clotrimazole)] fragment has been investigated against one Gram-positive bacterium and five Gram-negative bacteria. METHODS: The initial antimicrobial activity of the above-mentioned complexes was assessed by determining the minimum inhibitory and bactericidal concentrations using the broth microdilution method. Growth curves in the presence and absence of the complexes were performed to determine the effects of these complexes on the growth of the selected bacteria. A possible impact on cellular viability was determined by conducting the MTS assay on human monocytes. RESULTS: Three of the Mn complexes investigated (4-6) had good antimicrobial activities against all the bacteria tested, with values ranging from 1.79 to 61.95 µM with minimal toxicity. CONCLUSIONS: Due to the increased problem of antibiotic resistance and a lack of new antibacterial drugs with no toxicity, these results are exciting and show that these types of complexes can be an avenue to pursue in the future.


Assuntos
Manganês , Triazóis , Humanos , Triazóis/farmacologia , Manganês/farmacologia , Clotrimazol/farmacologia , Antibacterianos/farmacologia , Bactérias Gram-Negativas , Bactérias , Testes de Sensibilidade Microbiana
14.
GE Port J Gastroenterol ; 30(4): 311-315, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37767307

RESUMO

Introduction: Gastric metastases are quite infrequent. When arising from testicular germ cell tumors, gastric metastases are usually associated with nonseminomas. Case Report: A 45-year-old man presented with upper gastrointestinal bleeding, severe anemia, and elevated lactate dehydrogenase. Endoscopy revealed three atypical-looking gastric ulcers. Abdominal computed tomography showed an extensive heterogeneous retroperitoneal mass and a smaller one in the pelvis. Biopsies of both the ulcers and the retroperitoneal mass revealed a highly proliferative neoplasia of unknown origin. While the diagnostic work up was taking place, the patient complained of a testicular mass which was resected, after suspicious findings in the ultrasound. Histopathologic findings revealed a testicular seminoma. Revision of previous biopsies was compatible with metastatic seminoma to the stomach and the retroperitoneum. Discussion/Conclusion: Gastric metastasis arising from testicular seminoma is quite infrequent and usually diagnosed after the primary tumor is known. We report a rare case of a testicular seminoma presenting as upper gastrointestinal bleeding due to gastric metastases. This case highlights the importance of detailed anamnesis and physical examination in the differential diagnosis of atypical gastric ulcers with initial inconclusive work up and emphasizes an unusual manifestation of a germ cell malignancy.


Introdução: As metástases gástricas são bastante infrequentes. Quando são secundárias a tumores testiculares, geralmente as metástases gástricas associam-se a nãoseminomas. Caso Clínico: Um homem de 45 anos recorreu ao serviço de urgência por quadro de hemorragia digestiva alta, tendo-se detetado uma anemia grave e elevação da lactato desidrogenase. A endoscopia revelou três úlceras gástricas de aspeto atípico. A tomografia computorizada abdominal mostrou uma extensa massa heterogénea retroperitoneal e outra de menores dimensões na cavidade pélvica. Foram realizadas biópsias das úlceras gástricas e da massa retroperitoneal, sendo compatíveis com uma neoplasia altamente proliferativa de origem indeterminada. Durante a investigação etiológica, o doente referiu a deteção de uma massa testicular. Esta foi ressecada após a realização de ecografia com achados suspeitos. A histologia fez o diagnóstico de um seminoma testicular. A revisão das biópsias prévias foi compatível com metastização gástrica e retroperitoneal do seminoma. Discussão/Conclusão: A metastização gástrica com origem em seminomas do testículo é infrequente e geralmente é detetada após o diagnóstico do tumor primário. Apresenta-se um caso raro de manifestação inaugural de um seminoma testicular como hemorragia digestiva alta devido a metástases gástricas. Este caso evidencia a importância de uma anamnese e um exame objetivo detalhados no diagnóstico diferencial de úlceras gástricas atípicas com investigação inicial negativa, salientando também uma manifestação infrequente de uma neoplasia de células germinativas.

15.
PeerJ ; 11: e16048, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37744218

RESUMO

An incomplete, yet remarkably-sized dentated rostrum and associated partial cervical vertebrae of a pterosaur (ML 2554) were recently discovered from the Late Jurassic (Late Kimmeridgian-Early Tithonian) Lourinhã Formation of Praia do Caniçal, of central west Portugal. This specimen exhibits features such as a spatulated anterior expansion of the rostrum, robust comb-like dentition, and pronounced rims of the tooth alveoli, indicating gnathosaurine affinities. Based on its further unique tooth and dentary morphology, a new genus and species, Lusognathus almadrava gen. et spec. nov., is proposed, making this the first named pterosaur species found within Portugal. The presence of this taxon adds yet another element to the fluvio-deltaic lagoonal environment that has been suggested as representative of the Lourinhã Formation in the Late Jurassic, further contributing to the diversity and distribution of gnathosaurines worldwide.


Assuntos
Vértebras Cervicais , Alvéolo Dental , Portugal
16.
Antibiotics (Basel) ; 12(8)2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37627752

RESUMO

The rising demand for minimally processed, natural, and healthier food products has led to the search for alternative and multifunctional bioactive food components. Therefore, the present study focuses on the functional proprieties of a peptide fraction derived from Saccharomyces cerevisiae metabolism. The antimicrobial activity of the peptide fraction is evaluated against various foodborne pathogens, including Candida albicans, Candida krusei, Escherichia coli, Listeria monocytogenes, and Salmonella sp. The peptide fraction antioxidant properties are assessed using FRAP and DPPH scavenging capacity assays. Furthermore, the peptide fraction's cytotoxicity is evaluated in colorectal carcinoma and normal colon epithelial cells while its potential as an antidiabetic agent is investigated through α-amylase and α-glucosidase inhibitory assays. The results demonstrate that the 2-10 kDa peptide fraction exhibits antimicrobial effects against all tested microorganisms, except C. krusei. The minimal inhibitory concentration for E. coli, L. monocytogenes, and Salmonella sp. remains consistently low, at 0.25 mg/mL, while C. albicans requires a higher concentration of 1.0 mg/mL. Furthermore, the peptide fraction displays antioxidant activity, as evidenced by DPPH radical scavenging activity of 81.03%, and FRAP values of 1042.50 ± 32.5 µM TE/mL at 1.0 mg/mL. The peptide fraction exhibits no cytotoxicity in both tumor and non-tumoral human cells at a concentration up to 0.3 mg/mL. Moreover, the peptide fraction presents anti-inflammatory activity, significantly reducing the expression of the TNFα gene by more than 29.7% in non-stimulated colon cells and by 50% in lipopolysaccharide-stimulated colon cells. It also inhibits the activity of the carbohydrate digestive enzymes α-amylase (IC50 of 199.3 ± 0.9 µg/mL) and α-glucosidase (IC20 of 270.6 ± 6.0 µg/mL). Overall, the findings showed that the peptide fraction exhibits antibacterial, antioxidant, anti-inflammatory, and antidiabetic activity. This study represents a step forward in the evaluation of the functional biological properties of S. cerevisiae bioactive peptides.

17.
Pharmaceuticals (Basel) ; 16(7)2023 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-37513903

RESUMO

FucoPol, a fucose-rich polyanionic polysaccharide, was used for the first time for the preparation of hydrogel membranes (HMs) using Fe3+ as a crosslinking agent. This study evaluated the impact of Fe3+ and FucoPol concentrations on the HMs' strength. The results show that, above 1.5 g/L, Fe3+ concentration had a limited influence on the HMs' strength, and varying the FucoPol concentration had a more significant effect. Three different FucoPol concentrations (1.0, 1.75 and 2.5 wt.%) were combined with Fe3+ (1.5 g/L), resulting in HMs with a water content above 97 wt.% and an Fe3+ content up to 0.16 wt.%. HMs with lower FucoPol content exhibited a denser porous microstructure as the polymer concentration increased. Moreover, the low polymer content HM presented the highest swelling ratio (22.3 ± 1.8 g/g) and a lower hardness value (32.4 ± 5.8 kPa). However, improved mechanical properties (221.9 ± 10.2 kPa) along with a decrease in the swelling ratio (11.9 ± 1.6 g/g) were obtained for HMs with a higher polymer content. Furthermore, all HMs were non-cytotoxic and revealed anti-inflammatory activity. The incorporation of FucoPol as a structuring agent and bioactive ingredient in the development of HMs opens up new possibilities for its use in tissue engineering, drug delivery and wound care management.

18.
J Med Chem ; 66(13): 8580-8599, 2023 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-37311060

RESUMO

The work is focused on anticancer properties of dipicolinate (dipic)-based vanadium(IV) complexes [VO(dipic)(N∩N)] bearing different diimines (2-(1H-imidazol-2-yl)pyridine, 2-(2-pyridyl)benzimidazole, 1,10-phenanthroline-5,6-dione, 1,10-phenanthroline, and 2,2'-bipyridine), as well as differently 4,7-substituted 1,10-phenanthrolines. The antiproliferative effect of V(IV) systems was analyzed in different tumors (A2780, HCT116, and HCT116-DoxR) and normal (primary human dermal fibroblasts) cell lines, revealing a high cytotoxic effect of [VO(dipic)(N∩N)] with 4,7-dimethoxy-phen (5), 4,7-diphenyl-phen (6), and 1,10-phenanthroline (8) against HCT116-DoxR cells. The cytotoxicity differences between these complexes can be correlated with their different internalization by HCT116-DoxR cells. Worthy of note, these three complexes were found to (i) induce cell death through apoptosis and autophagy pathways, namely, through ROS production; (ii) not to be cytostatic; (iii) to interact with the BSA protein; (iv) do not promote tumor cell migration or a pro-angiogenic capability; (v) show a slight in vivo anti-angiogenic capability, and (vi) do not show in vivo toxicity in a chicken embryo.


Assuntos
Antineoplásicos , Complexos de Coordenação , Neoplasias Ovarianas , Animais , Embrião de Galinha , Feminino , Humanos , Antineoplásicos/farmacologia , Apoptose , Linhagem Celular Tumoral , Complexos de Coordenação/toxicidade , Fenantrolinas/farmacologia , Vanádio
19.
J Inorg Biochem ; 245: 112255, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37196411

RESUMO

The ruthenium arene fragment is a rich source for the design of anticancer drugs; in this design, the co-ligand is a critical factor for obtaining effective anticancer complexes. In comparison with other types of ligands, N-heterocyclic carbenes (NHCs) have been less explored, despite the versatility in structural modifications and the marked stabilization of metal ions, being these characteristics important for the design of metal drugs. However, notable advances have been made in the development of NHC Ruthenium arene as anticancer agents. These advances include high antitumor activities, proven both in in vitro and in in vivo models and, in some cases, with marked selectivity against tumorigenic cells. The versatility of the structure has played a fundamental role, since they have allowed a selective interaction with their molecular targets through, for example, bio-conjugation with known anticancer molecules. For this reason, the structure-activity relationship of the imidazole, benzimidazole, and abnormal NHC ruthenium (II) η6-arene complexes have been studied. Taking into account this study, several synthetic aspects are provided to contribute to the next generations of this kind of complexes. Moreover, in recent years nanotechnology has provided innovative nanomedicines, where half-sandwich Ruthenium(II) complexes are paving their way. In this review, the recent developments in nanomaterials functionalized with Ruthenium complexes for targeted drug delivery to tumors will also be highlighted.


Assuntos
Antineoplásicos , Complexos de Coordenação , Rutênio , Estrutura Molecular , Rutênio/química , Relação Estrutura-Atividade , Antineoplásicos/farmacologia , Antineoplásicos/química , Complexos de Coordenação/química , Ligantes
20.
Anal Bioanal Chem ; 415(14): 2849-2863, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37097304

RESUMO

The success of personalized medicine depends on the discovery of biomarkers that allow oncologists to identify patients that will benefit from a particular targeted drug. Molecular tests are mostly performed using tumor samples, which may not be representative of the tumor's temporal and spatial heterogeneity. Liquid biopsies, and particularly the analysis of circulating tumor DNA, are emerging as an interesting means for diagnosis, prognosis, and predictive biomarker discovery. In this study, the amplification refractory mutation system (ARMS) coupled with high-resolution melting analysis (HRMA) was developed for detecting two of the most relevant KRAS mutations in codon 12. After optimization with commercial cancer cell lines, KRAS mutation screening was validated in tumor and plasma samples collected from patients with pancreatic ductal adenocarcinoma (PDAC), and the results were compared to those obtained by Sanger sequencing (SS) and droplet digital polymerase chain reaction (ddPCR). The developed ARMS-HRMA methodology stands out for its simplicity and reduced time to result when compared to both SS and ddPCR but showing high sensitivity and specificity for the detection of mutations in tumor and plasma samples. In fact, ARMS-HRMA scored 3 more mutations compared to SS (tumor samples T6, T7, and T12) and one more compared to ddPCR (tumor sample T7) in DNA extracted from tumors. For ctDNA from plasma samples, insufficient genetic material prevented the screening of all samples. Still, ARMS-HRMA allowed for scoring more mutations in comparison to SS and 1 more mutation in comparison to ddPCR (plasma sample P7). We propose that ARMS-HRMA might be used as a sensitive, specific, and simple method for the screening of low-level mutations in liquid biopsies, suitable for improving diagnosis and prognosis schemes.


Assuntos
Neoplasias Pancreáticas , Proteínas Proto-Oncogênicas p21(ras) , Humanos , Proteínas Proto-Oncogênicas p21(ras)/genética , Prognóstico , Reação em Cadeia da Polimerase/métodos , Mutação , Biomarcadores Tumorais/genética
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